The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Engine water pumps are typically belt-driven centrifugal pumps that circulate coolant through an engine to cool the engine. Coolant is received through an inlet located near the center of a pump, and an impeller in the pump forces the coolant to the outside of the pump. Coolant is received from a radiator, and coolant exiting the pump flows through an engine block and a cylinder head before returning to the radiator.
In a conventional water pump, the impeller is always engaged with a belt-driven pulley. Thus, the pump circulates coolant through the engine whenever the engine is running. In contrast, an electric water pump is not driven by an engine. Thus, an electric water pump may be switched on or off regardless of whether the engine is running. The electric water pump may be switched off to improve fuel economy, and the electric water pump may be switched on to cool the engine.